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In this work, the gravitational field is investigated in detailed and the quantum mechanics equation under the gravitational field has been derived. Then, the Schrodinger and Dirac equations are accordantly solved under the gravitational field condition by separating variables. As a result, the Rydberg formula is deduced in such conditions, which proves that the change of the external gravitational field intensity will cause the overall spectral movement. Obviously, the partial redshift of quasar spectrum should assign to this effect. Furthermore, by applying this gravitational field together with the energy and mass concepts into the symmetry, gravity theory and gauge theory, it is deduced that the interaction of “gravity” between matter and anti-matter is repulsive force, which is the originator of the accelerated expansion phenomenon for dark energy in the universe. It is found that the calculated cosmological constant is a small variable related to the radial and angular direction of the universe, and the “spontaneous breaking of vacuum symmetry” is caused by this gravitational field. Further, the gravitational field lead to the non-conservation of weak action parity. The equal number of baryon and antibaryon as well as the energy conservation in the universe are confirmed. In this work, the gravitational field is introduced into quantum theory, which will promote the integrality of the quantum mechanics, and explain the dark energy phenomenon constitutionally. This study will push the astrophysical theory and the gauge theory of particle physics for the further study of energy level, basic particle structure, and quantum gravity theory.

Components and crystal structures of the intermetallic phases in a gravity die-cast Mg−6.0Zn−1.5Nd−0.5Zr (wt%) alloy were investigated using transmission electron microscopy. The results indicate that this alloy has multiple intermetallic phases and various inner faults. Totally, six eutectoid intermetallic phases, namely W (MgNdZn3), T (Mg39Zn55Nd6), (Mg,Zr)Zn2, Z (Mg28Zn65Nd7), H2 (Mg15Zn70Nd15), and H1 (Mg24Zn64Nd11), were simultaneously observed at grain boundaries, and six precipitates (Z, Mg7Zn3, T, Mg4Zn7, β1′-MgZn2 and β2′-MgZn2) were found in α-Mg grains. Furthermore, faults like sub-grain boundaries, orientation domains (coherent with the same matching plane but with different orientations), stacking faults and twins were observed in the eutectoid intermetallic phases. Finally, some new orientation relationships between the known intermetallic phases were revealed. This paper can provide new insight into alloy design for Mg−Zn−RE (RE: rare earth) based alloys.

Twinning and precipitation play important roles in deformation and strengthening of magnesium alloys. In this work, interfacial precipitation in {10 1 ¯ 2} twin boundaries (TBs) of a cold-stamped Mg−12Gd−1.2Zn−0.4Zr alloy was investigated using atomic-resolution high-angle annular dark-field scanning transmission electron microscopy. Extended periodic segregation of Gd + Zn atoms in the ~86.2° {10 1 ¯ 2} TBs with basal-prismatic facets and in the symmetric tilting TBs (obviously > 86.2°) frequently occurred, resulted in the formation of new interfacial phases, namely βTB’ having a monoclinic structure in the TBs with two segregation layers and βTB having a tetragonal structure in the TBs with three or more segregation layers. The formation of βTB clearly accelerates peak-aging and improves the alloy's strength.

The emerging polyethylenimine (PEI)-functionalized solid adsorbents have witnessed significant development in the implementation of CO2 capture and separation because of their decent adsorption capacity, recyclability, and scalability. As an indispensable substrate, the importance of selecting porous solid supports in PEI functionalization for CO2 adsorption was commonly overlooked in many previous investigations, which instead emphasized screening amine types or developing complex porous materials. To this end, we scrutinized the critical role of different commercial porous supports (silica, alumina, activated carbon, and polymeric resins) in PEI impregnation in this study, taking into account multiple perspectives. Hereinto, the present results identified that abundant larger pore structures and surface functional groups were conducive to loading a considerable amount of PEI molecules. Various supports after PEI functionalization had great differences in adsorption capacities, amine efficiencies, and the corresponding optimal temperatures. In addition, more attention was paid to the role of porous supports in long-term stability during the consecutive adsorption-regeneration cycles, while N2 and CO2 purging as regeneration strategies, respectively. Especially, CO2-induced degradation due to urea species formation was specifically recognized in a SiO2-based adsorbent, which would induce serious concerns in CO2 cyclic capture. On the other side, we also confirmed that adopting conventional porous supports, for example, HP20, could achieve superior adsorption performance (above 4 mmol CO2/g) and cyclic stability (around 1% loss after 30 cycles) rather than the ones synthesized through complex approaches, which ensured the availability and scalability of PEI-functionalized CO2 adsorbents.

As a narrow band gap semiconductor, wurtzite β-CuGaO2 has drawn increasing attention in the area of solar energy. Although β-CuGaO2 has been theoretically predicted to possess ferroelectric polarization, its experimental ferroelectric characterization and practical applications have not yet been presented. Herein, firstly we experimentally confirmed its ferroelectric property via hysteresis loop measurement. The result showed a remanent polarization value of 10.20 μC·cm−2 with low coercive electric field of 6.45 kV·cm−1 at 20 Hz at room temperature, while the leakage current density (J) value was found to be 1.188 A·cm−2, which suggested the property of a larger remnant polarization with low coercive electric field than current value if the compactness was strengthened. Then, the synergistic effect of ferroelectric and semiconductor was comparatively highlighted by the experiment of pollutant degradation. Within 30 min, methyl orange degradation efficiency had reached 30.73% only in the case of spontaneous polarization (electricity), while it could reach 67.58% under the effect of pre-polarized β-CuGaO2 powder due to the modulating orientation of ferroelectric domains. Once irradiated (light), it was up to 92% within 30 min; in comparison, it merely took 16 min up to 92% degradation efficiency under both illumination and pre-polarization. If without illumination, it was 92.01% with 30 min in the condition of ordinary ultrasonic vibration (force) while under both illumination and ultrasonic vibration, only 11 min was spent to reach 92.79% degradation efficiency. All these results felicitously indicated that β-CuGaO2 had fascinating potential in energy harvesting (such as electricity, light, force) and transformation as wastewater environment remediation catalyst.

In recent years, global warming has become an important topic of public concern. As one of the most promising carbon capture technologies, solid amine adsorbents have received a lot of attention because of their high adsorption capacity, excellent selectivity, and low energy cost, which is committed to sustainable development. The preparation methods and support materials can influence the thermal stability and adsorption capacity of solid amine adsorbents. As a supporting material, it needs to meet the requirements of high pore volume and abundant hydroxyl groups. Industrial and biomass waste are expected to be a novel and cheap raw material source, contributing both carbon dioxide capture and waste recycling. The applied range of solid amine adsorbents has been widened from flue gas to biogas and ambient air, which require different research focuses, including strengthening the selectivity of CO

Biodrying is a promising method that produces bio-stabilized output with minimum pretreatment requirements. In this study, a hot-air supply system was added to the traditional biodrying process for kitchen waste, which showed significant reduction in moisture content in 5 days (maximum reduction of 37.45%). A series of experiments was conducted to optimize the hot-air biodrying system utilizing different aeration rates, temperatures, and mixing ratios of feedstock to bulking agents. The results showed that a 65 °C aeration temperature led to the highest water removal rate and low volatile solids consumption rate, with the biodrying index reaching 4.9 g water per gram of volatile solids. On the other hand, evaluation of the overall biodrying efficiency based on the weight loss and bio-stabilization showed that intermittent aeration temperature at 55 °C performed best, offering suitable conditions for water evaporation and bio-degradation. In combination with a flow rate of 0.8 L/kg*min and 1:1 mixing ratio, these conditions resulted in the maximum volatile solids consumption of 26.26% in 5 days. The volatile solids consumption and 34.47% water removal rate of the trial had contributed to a total of 64.13% weight loss. The weight loss was even higher than that of a conventional biodrying system which was conducted for more than 14 days.

The emerging polyethylenimine (PEI)-functionalized solid adsorbents have witnessed significant development in the implementation of CO

The commercial steel was processed by three different Q&P heat treatments and three kinds of steels with different microstructures and mechanical properties were obtained. Among them, two steel samples contain bainite and ferrite matrix, fresh martensite and retained austenite, while the other possesses tempered martensite and ferrite matrix, fresh martensite and retained austenite. Comparing the content of retained austenite in these samples, the highest volume fraction was obtained in the sample with bainite matrix and a higher partitioning temperature. The mechanical property result shows that the yield strength for three steel samples had little difference, but their elongations were quite different. The steel with most retained austenite exhibits a good combination of yield strength and ductility.

Municipal solid waste incineration (MSWI) fly ash is classified as hazardous waste and requires proper treatments. Sintering of MSWI fly ash for the production of lightweight aggregate (LWA) is a promising treatment technology, while the dependence on natural bloating clay to produce high quality LWA has limited its wide application. In this study, by using SiC as a bloating agent, normal clay could be used to produce super-lightweight aggregate (bulk density500 kg/m

Effects of various Sm additions on microstructures and mechanical properties of a hot-extruded Mg–14Gd−0.5Zr alloy were studied in this work. The results indicate that Sm addition firstly clearly improves the strength and then decrease as the Sm content increases at both room temperature and high temperatures. The highest yield strength was obtained to be ∼495 MPa and ∼512 MPa under tension and compression, respectively, at room temperature with the Sm concentration of 1 wt.% while those were to be 384 MPa and 248 MPa at 250 °C and 300 °C, respectively, with the Sm content of 0.5 wt.%. Electron backscatter diffraction mappings reveal that Sm addition significantly promotes dynamic recrystallization, resulted in much more fine recrystallized grains and lower texture intensity. Furthermore, transmission electron microscopy observations show that Sm addition increases dynamic precipitates particularly in non-recrystallized regions, leading to relatively less aging precipitates during artificial peak-aging. Finally, discussion based on grain boundary strengthening and dispersion strengthening suggests that Sm addition improving the yield strength of the extruded Mg–14Gd−0.5Zr alloy is mainly attributed to more grain boundaries and dynamic precipitates at room temperature and high temperatures, respectively.

Effects of 0.5 wt% La addition on microstructures and mechanical properties of a traditional hot-extruded Mg–9Gd–3Y–0.5Zr alloy were thoroughly investigated in this work. The results indicate that minor La addition obviously improves the alloy’s mechanical performance at room temperature, accomplished an ultra-high tensile yield strength of 480 MPa with the elongation of ~6%, although leading to much lower high-temperature strength. Microstructural analysis reveals that after extrusion, minor La addition leads to a significantly higher level of recrystallization (the volume fraction is improved from 21% to 68%), much finer dynamically recrystallized (DRXed) grains (the average sizes are refined from 4.12 µm to 3.26 µm), and also finer non-recrystallization stripes. La addition promoting recrystallization is mainly attributed to the finer grains and much more intermetallics not only at grain boundaries but also in α-Mg grains of the ingots before extrusion. During peak-aging, minor La addition does not change intermetallics/precipitates in both DRXed grains and non-recrystallized regions except some extra coarse Mg17La2 particles mainly in extrusion stringers. Therefore, minor La addition improving both strength and ductility of the hot-extruded Mg–9Gd–3Y–0.5Zr alloy at room temperature is mainly by grain-refinement strengthening which is also the underlying cause for the lower work hardening coefficient, high-temperature strength but higher ductility.

Phase transformation in structural alloys is of practical significance for their security services. Understanding phase transformation of strengthening intermetallic phases and its influence on mechanical properties is therefore crucial for the alloys’ safe applications and further development. In this work, investigations using an aberration-corrected scanning transmission electron microscopy combined with density functional theory calculations reveal that the strengthening intermetallic phase, η-Al3La, of a die-casting Mg − 3.5Al − 4.2La alloy is metastable, and it will transform to α-Al11La3 via an intermediate phase, e-Al2.12La0.88, during annealing at 250 °C. For each transformation step, two orientation relationships are obeyed due to different nucleation sites or temperatures, or because of similar interfacial energy. Furthermore, a new planar fault, namely monolayer twin (MT), was observed, and it not only offer the nucleation site for e-Al2.12La0.88 and the fast diffusion path for Al atoms, but also provide driving force for overcoming the energy barrier of η → e → α transformation. Finally, both intermediate and product phases will obstruct the η-Al3La phase delivering 〈c + a〉 dislocations, and the level of solute Al atoms in Mg matrix will be clearly lowered during phase transformation, which result in deterioration in plasticity and creep resistance, respectively.